Lifting jack



Nnv.` 26, 1929. A. c. HOPKINS LIFT'ING JACK Filed April l, 1927l N UVV 7J fia@ Patented Nov. 26, 1929 titten ARTHUR C. HOPKINS, NILES, MICHGAN, ASSL'GNOR TO NATIONAL STANDARD COMPANY, OF NILES, MGHGAN LIFTING TACK Application led April l,

The main objects of this invention are:

First, to provide an improved lifting ack which is very compact when collapsed and at the same time has a considerable lift.

`Second, to provide an improved lifting j ack which is very powerful.

Third, to provide an improved lifting Jack having screw extension means in which the threaded parts are completely housed.

Objects relating to details and economies of construction and operation of my invention will appear from the detailed description to follow.

rlhe invention is defined and pointed out in the claims.

A structure which is a preferred embodiment of my invention is illustrated in the accompanying drawing, forming a part of this specification, in which:

Fig. 1 is a detail view mainly in vertical section of my improved lifting ack collapsed, on line 1-1 of Fig. 2.

Fig. 2 is a horizontal section on a line corresponding to line 2-2 of Fig. 1.

Fig. 3 is a detail section on a line corresponding to line 3-3 of Figs. 1 and 4..

Fig. 4 is a fragmentary side elevation of my improved lifting jack extended, parts being broken away to show structural details.

In the embodiment of my invent-ion illustrated, the standard 1 is provided with a gear housing2 at its lower end, and with a peripheral flange 3 resting upon and secured to the base plate 4 by the bolts or rivets 5. This standard has internal screw threads 6 and an inturned flange 7 at the top, the flange having opposed notches 8 therein.

The driving spindle 9 is disposed vertical- Y ly within the standard, its lower end being iournaled at 10 in the base plate, the spindle being provided with a beveled gear 11. lhe driving pinion 12 is arranged to mesh .with this gear 11, the driving gear being Journuarled in the bearing 13 of the gear housing and provided with a socket 14 adapted to receive the shaft 15 of a crank.

On the spindle is a driving screw 16 h av ing a lower or bottom portion 17 coacting with the threads of the standard. The screw has a threaded barrel-like upper portion 13 Serial No. 180,192.

lifting member 20 coact. This barrel-like portion 13 is reversely threaded relative to the threads of the portion 17.

The lifting member 2O is tubular to telescope with the portion 18 of the screw and is provided with a head 21 at its upper end.

The lifting member is provided with alongitudinal rib 22 which engages the notch 23 in the inwardly turned flange 24 in the upper end of the sleeve-li re housing 25, this sleeve being telescopingly associated with the standard and with the lifting member. The rib 22 engaging the notch 23 prevents rotation of the lifting member relative to the sleeve; the sleeve in turn is held against rotation by its longitudinal ribs 26which engage notches 8 in the inturned flange 7 at the upper end of the standard.

rifhe lifting member has an out-turned flange 27 co'acting with the inturned flange 24 of thehousing sleeve to provide stops.

`rlie out-turned flange 28 at the lower end of lthe sleeve engages the flange 7 ofthe standard to provide stops,so that the sleeve member 25 performs the function of a housing enclosing the screw, a stop limiting th-e eX- tension of the jack and supporting the lift. ing member against rotation so that as the screw is rotated through the spindle, it not only travels up in thestandard owing to the engagement of its threaded portion 17 with the threads of the standard, but the lifting member is simultaneously projected, so that l not only provide va jack which is very pow-V erful but one which is rapidly extendedand retracted. i

I have illustrated and described my improved jack'in anembodiment which 1 consider very practical. I have not attempted i wardly projecting flange at its upper end, a vertically disposed driving spindle rotatably mounted in said standard and provided with .a beveled gear at its lower end, a driving gear mounted on said standard to coact with said gear on said spindle, an actuating screw having splined driving engagement with said` spindle and provided with a threaded lower portion coacting with the threads of said standard and with an oppositely threaded upper portion, a hollow lifting member telescopingly associated with the upper portion of said actuating screw and having threaded engagement therewith, said lifting member having an out-turned flange at its lower end and 1a longitudinal rib., and a housing sleeve embracing said upper portion of said screw and telescopingly associated therewith and with said standard, said sleeve having an outturned flange at its lower .end coacting with the inturned flange at the top vof said standard, andan inturned flange at its upper end coacting with said flange at the lower end of said lifting member, said flanges coacting to provide sto s, said sleeve having a longitudinal rib, Asai flange on said sleeve being notched .to coact with said rib on said lifting member and said flange on said standard being notched to coact with said rib on said sleeve whereby the sleeve Vvand lifting member are supported against rotation.

2. YIn a lifting ack, the combination ofan internally threaded standard having an inwardly projecting flange at its upper end, a vertically disposed driving spindle rotatably mounted in said standard, an actuating screw having splined driving `engagement with said Spindle and provided with a threaded lower portion coacting with the threads of said standard and with an oppositely threaded upper portion, a hollow lifting member telescopingly associated with the upper portion of said actuating screw and having threaded engagement therewith, said lifting member havingan out-turned flange at its lower end anda longitudinal rib, and a housing sleeve embracing said upper portion of ysaid screw and telescopingly associated therewith and with said standard, said sleeve having an outturned flange at its lower end coacting with the inturned flange at the'top of said standard, and an inturned flange at its upper end coacting with said flange at the lower end of said lifting member, said flanges coacting to provide stops, said sleeve having a longitudinal rib, said flange on said sleeve being Y notched to coact with said rib on said lifting member and said flange on said standard being notched to coact with said rib on said sleeve wherebyV the sleeve and lifting inember are supported against rotation.

A3. In a lifting jack, the combination ofan internally threaded standard, a vertically disposed driving spindle, an actuating' screw having splined driving engagement with said spindle and provided with a threaded lower portion coacting with the threads of the standard and with an oppositely threaded upper portion, al lifting member having threaded engagement with the upper portion of the screw and provided with a longitudinal rib, and a housing member telescopingly associated with said standard and lifting member and provided with a longitudinal rib and with stop means `coacting Ywi-th'said standard and lifting member, said housing member having means coacting with said rib on said lifting `member to prevent rotation of the lifting member, said. standard having means coacting with said rib on said housing member to prevent rotation Vof vthe housing member.

In witness whereof I have hereunto set my hand.Y l

ARTHUR C. HOPKINS.. 

